A sensational new document proving with “near certainty" that Princess Diana was pregnant at the time of her death has been found in France.

An investigative journalist, formerly of the reputable Paris Match magazine, claims to have uncovered the explosive proof from archives at the hospital where the Princess was taken after the crash on the night of August 31 1997.

The document has previously remained hidden for 10 years due to “ethical and privacy” concerns, according to respected investigative reporter Chris Lafaille.

The journalist makes the shocking claims in a new book called Diana, the Inquiry They Never Published to coincide with the tenth anniversary of her death later this month.

Diana and Dodi share an intimate moment on board his yacht

He said: “It is a near certainty Diana was nine to 10 weeks pregnant at the time she died, according to papers from the Paris Public Hospitals archives.

“The document dated August 31 1997 was sent to the then minister of the interior Jean-Pierre Chevenement, with copies to health minister Bernard Kouchner, foreign affairs minister Hubert Vedrine and Paris police chief Martine Monteil.”

He added: “It has never been claimed or proved to be a fake.”

It has never been claimed or proved to be a fake

Chris Lafaille

The revelation would explain why the Princess was illegally embalmed in the hours after her death. The process, carried out contrary to French law, meant any potential pregnancy test results would have been rendered invalid.

The pregnancy claims address one of the key questions set out by the coroner to be answered at the inquest into Diana’s death, which is due to begin in October. Coroner Lord Justice Scott Baker recently listed 20 key issues he intends to explore during up to six months of hearings.

Lord Justice Scott Baker said he wanted to deal with allegations that the Princess was murdered in a criminal conspiracy.

As a result the hearings will examine whether Diana feared for her life, whether she was pregnant and whether chauffeur Henri Paul was drunk or on drugs. They include many of the issues highlighted in a Daily Express crusade for the truth.

Last night, a spokeswoman for Harrods boss Mohamed Al Fayed, whose son Dodi also died in the crash, said: “If there is any new evidence it should be handed to the coroner so he can properly conduct the inquest.” Other questions to be addressed include whether a Fiat Uno or flashing light contributed to the crash.

The coroner wants to tackle such issues so that he can either confirm or allay the public’s suspicions amid claims that Diana and Dodi Fayed were murdered by British agents because the couple were about to get engaged and the Princess was pregnant.

The new revelations will raise further speculation as to who might have been father to Diana’s unborn child. The Princess had recently been holidaying with Dodi Fayed prior to the fatal crash in Paris.

Mr Al Fayed has long claimed that the Princess was pregnant – a claim dismissed by the multi-million- pound Paget Inquiry led by former Met Police Comm-issioner Lord Stevens.

The startling new claims come almost 10 years to the day after the Princess’s black Mercedes limo ploughed into a concrete pillar in the Alma tunnel while being pursued by 10 paparazzi.

A four-year investigation by Paris magistrate Herve Stephan ruled that high speed and a cocktail of drugs and alcohol taken by chauffeur Henri Paul caused the crash.

But findings of the official inquiries have come under attack, with many believing the Princess was murdered by the British establishment to prevent her marrying a muslim.

Mr Al Fayed claims the pair were killed in a plot hatched by the British Establishment, headed by Prince Philip.

Mr Al Fayed was bitterly disappointed by Lord Stevens’ report into the deaths which he branded a whitewash as it failed to address many key questions.

These included why the driver of a Fiat Uno which clipped the Mercedes has never been found and why none of the original 18 eyewitnesses were interviewed again by the Paget team.

Other issues include whether or not chauffeur Henri Paul’s blood samples were switched or why the blood contained such high levels of carbon monoxid.